A Hong Kong janitor accused of taking part in an unlawful assembly during the 2019 social unrest cannot be held liable for the crime due to his mental disability, a magistrate has found.

Lee Kai-fat is the first defendant to be exempt from making a plea in a case stemming from the citywide protests that year on grounds of mental incapacity.

West Kowloon Court Magistrate Lau Suk-han on Friday held that the 33-year-old was unfit to enter a plea, as he was unable to fully understand the three charges laid against him in relation to his involvement in the protest outside Mong Kok Police Station on October 12, 2019.

Lau also expressed concern the accused might be unable to effectively instruct his lawyers and challenge the prosecution’s evidence during the trial, as he could not recall most parts of the incident due to memory loss.

“I have reservations as to whether the defendant is able to provide instructions to his lawyers, challenge the evidence of witnesses, and follow the trial,” Lau said. “For those reasons, I find the defendant unfit to stand trial.”

The court had heard that Lee was diagnosed with mild intellectual disability at the age of five, with his cognitive ability as an adult equivalent to a child aged between nine and 11.

Despite the ruling, the defendant will still face a hearing which, instead of determining criminal liability, will decide whether it is in the public interest to send him for psychiatric treatment.

Lee has been charged with taking part in an unlawful assembly, possessing an offensive weapon in a public place, and using a facial covering in an unlawful assembly.

On the day in question, Lee was caught using a laser pointer to shine bright lights at the police facility in an illegal gathering of around 100 protesters.

Lee said he had gone to the police station to “meet girls”, and that the laser pointer had been given to him by someone on the scene. He also said he did not know how to use a laser pointer and only knew it could produce some beautiful lights.

Following a series of interviews conducted last year, two psychiatrists hired by the defence suggested the defendant was unfit to enter a plea, whereas two other doctors for the prosecution opined that he was ready for trial as he understood the charges and his legal rights.

But in another round of interviews earlier this year, the two doctors for the prosecution found Lee unable to comprehend the allegations and potential consequences if he were found guilty, especially in relation to the government mask ban imposed a week before the incident.

The prosecution urged the magistrate to disregard the latest psychiatric findings by its own experts, suggesting the defendant might have simply been unwilling to cooperate.

It also said the accused had sufficient understanding of the criminal procedures, citing his conviction in June last year in a separate case related to the protests, in which he was jailed for possession of a suspected petrol bomb and a laser pen.

While rejecting some evidence of the experts from both sides, Lau accepted that Lee’s mental ailment had affected his memory and that he could not properly understand the charges given his limited cognitive skills.

She stressed that her decision was not bound by any previous court rulings, as her task was to determine whether the defendant at present had the ability to handle a trial.

Lee will return to Kwun Tong Court on September 6. He faces up to three years in a psychiatric hospital should the magistrate be satisfied he had committed the criminal acts as charged, but will be spared a criminal record.